As I mentioned a week ago, Target has marked down the regular 3DS to $129.99, a $40 reduction of its retail value. This includes all colors -- aqua, black, red, pink, and Prince edition -- for what is doubtless to be a limited time.
If you can't make it to Target this week, Best Buy will be running the same deal from Sunday, December 9, through Saturday, December 15, alongside the discounted 3DS XL. Also, you'll save $20 if you buy any two of the following titles: Paper Mario: Sticker Star, Super Mario 3D Land, New Super Mario Bros. 2, Style Savvy: Trendsetters, Mario Kart 7, and Professor Layton and the Miracle Mask.
According to Cheap Ass Gamer, there are other Best Buy deals as well, but you ought to know where my focus lies by now.